Improving Your Scanning Skills
Dear Fellow Echocardiographers,
When teaching echocardiography, we noticed that trainees often make the same mistakes. In this and the upcoming blog post, we will provide you with little tips and tricks to improve your skills. Follow these steps and your imaging abilities will improve considerably. In this post, we want to focus on “how to adjust the scanner settings” during imaging...
Know Your Scanner!
The most important determinant of image quality is the technical skill of the investigator; still, much can be improved if you choose the right settings. Modern scanners provide many features and ways to optimize the image. Some are really important while others are of minor relevance. Actually, we only use a handful of the buttons ourselves. Still, you have to know which knobs are important and how they affect image quality. So as a general rule: take your time to learn your scanner and stay in contact with the application specialists! Not only will this improve your imaging skills but it will also speed up the examination.
So lets start with a few fundamental rules:
- Optimize you gain settings: It might seem appealing to turn down the gain so that the cavities of the heart look completely black. But consider that you lose important low intensity signals by doing so! Try to stay somewhere in the middle-range.
- Choose the right depth: so you can image the structures you are actually interested in. If you increase depth, your frame rate and resolution will go down.
- Keep the sector width as small as possible: as with depth, increasing sector width will compromise frame rate and resolution. Decide what you want to image and adjust your sector accordingly.
- Keep the color region of interest as small as possible: Why? Well, simply because decreasing the region of interest will considerably improve your color’s resolution and frame rate.
- Choose the right imaging frequency: most transducers allow several image frequencies to be used. Use high frequencies for slim patients and lower frequencies for patients who are obese! Remember penetration and resolution are functions of imaging frequency!
- Reduce the 2D gain if you use color Doppler: this enhances the color display!
- Fiddle with the Pulse Repetition Frequency (PRF): The PRF defines the aliasing velocity (limit) of the color display. If you reduce the PRF, you will be more sensitive for low velocity flow (e.g., systemic venous flow. pulmonic venous flow, ASD jets). But, stick with the original PRF setting if you assess high velocity jets (e.g., regurgitation jets). The size of a jet depends on the PRF setting. If the PRF is low, jets look larger than if the PRF is high! So the PRF setting greatly influences the visual quantification of jets.
As you see, many of the functions strongly relate to the physical principles of ultrasound. We strongly recommend to learn these basic principles. On our e-learning platform we dedicated a fairly large chapter to this issue. In the next post we will focus on how patient-breathing can be used to optimize your image.